The evidence base for integrative forms of psychotherapy for obsessive morbid jealousy (OMJ) is very limited and so this study sought to examine the effectiveness of cognitive analytic therapy (CAT) in a small case series. Three A/B with extended follow-up single case experimental designs (SCEDs) were completed, with 1 male and 2 female patients presenting with OMJ. Results indicate that on the daily ideographic jealousy measures (across and within each case) there was evidence of significant reductions in morbid jealousy (and other associated symptoms) during the treatment phase. Treatment effects were also seen to be maintained over the follow-up period in these ideographic measures. On the primary nomothetic measure, all cases were classed as nonjealous by follow-up. Partner violence was extinguished across all cases. This article provides evidence of CAT offering promise as a suitable OMJ treatment option. Methodological limitations, theoretical insights, and treatment implications are all discussed.